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-rw-r--r--arch/powerpc/xmon/Makefile2
-rw-r--r--arch/powerpc/xmon/xmon.c259
-rw-r--r--arch/powerpc/xmon/xmon_bpts.S11
-rw-r--r--arch/powerpc/xmon/xmon_bpts.h14
4 files changed, 193 insertions, 93 deletions
diff --git a/arch/powerpc/xmon/Makefile b/arch/powerpc/xmon/Makefile
index 6f9cccea54f3..89c76ca35640 100644
--- a/arch/powerpc/xmon/Makefile
+++ b/arch/powerpc/xmon/Makefile
@@ -18,7 +18,7 @@ endif
ccflags-$(CONFIG_PPC64) := $(NO_MINIMAL_TOC)
-obj-y += xmon.o nonstdio.o spr_access.o
+obj-y += xmon.o nonstdio.o spr_access.o xmon_bpts.o
ifdef CONFIG_XMON_DISASSEMBLY
obj-y += ppc-dis.o ppc-opc.o
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index 7af840c0fc93..7efe4bc3ccf6 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -35,7 +35,6 @@
#include <asm/machdep.h>
#include <asm/xmon.h>
#include <asm/processor.h>
-#include <asm/pgtable.h>
#include <asm/mmu.h>
#include <asm/mmu_context.h>
#include <asm/plpar_wrappers.h>
@@ -54,6 +53,7 @@
#include <asm/firmware.h>
#include <asm/code-patching.h>
#include <asm/sections.h>
+#include <asm/inst.h>
#ifdef CONFIG_PPC64
#include <asm/hvcall.h>
@@ -62,6 +62,7 @@
#include "nonstdio.h"
#include "dis-asm.h"
+#include "xmon_bpts.h"
#ifdef CONFIG_SMP
static cpumask_t cpus_in_xmon = CPU_MASK_NONE;
@@ -98,7 +99,7 @@ static long *xmon_fault_jmp[NR_CPUS];
/* Breakpoint stuff */
struct bpt {
unsigned long address;
- unsigned int instr[2];
+ struct ppc_inst *instr;
atomic_t ref_count;
int enabled;
unsigned long pad;
@@ -109,9 +110,8 @@ struct bpt {
#define BP_TRAP 2
#define BP_DABR 4
-#define NBPTS 256
static struct bpt bpts[NBPTS];
-static struct bpt dabr;
+static struct bpt dabr[HBP_NUM_MAX];
static struct bpt *iabr;
static unsigned bpinstr = 0x7fe00008; /* trap */
@@ -121,6 +121,7 @@ static unsigned bpinstr = 0x7fe00008; /* trap */
static int cmds(struct pt_regs *);
static int mread(unsigned long, void *, int);
static int mwrite(unsigned long, void *, int);
+static int mread_instr(unsigned long, struct ppc_inst *);
static int handle_fault(struct pt_regs *);
static void byterev(unsigned char *, int);
static void memex(void);
@@ -326,11 +327,6 @@ static inline void sync(void)
asm volatile("sync; isync");
}
-static inline void store_inst(void *p)
-{
- asm volatile ("dcbst 0,%0; sync; icbi 0,%0; isync" : : "r" (p));
-}
-
static inline void cflush(void *p)
{
asm volatile ("dcbf 0,%0; icbi 0,%0" : : "r" (p));
@@ -706,13 +702,13 @@ static int xmon_core(struct pt_regs *regs, int fromipi)
if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) == (MSR_IR|MSR_64BIT)) {
bp = at_breakpoint(regs->nip);
if (bp != NULL) {
- int stepped = emulate_step(regs, bp->instr[0]);
+ int stepped = emulate_step(regs, ppc_inst_read(bp->instr));
if (stepped == 0) {
regs->nip = (unsigned long) &bp->instr[0];
atomic_inc(&bp->ref_count);
} else if (stepped < 0) {
printf("Couldn't single-step %s instruction\n",
- (IS_RFID(bp->instr[0])? "rfid": "mtmsrd"));
+ IS_RFID(ppc_inst_read(bp->instr))? "rfid": "mtmsrd");
}
}
}
@@ -761,8 +757,8 @@ static int xmon_bpt(struct pt_regs *regs)
/* Are we at the trap at bp->instr[1] for some bp? */
bp = in_breakpoint_table(regs->nip, &offset);
- if (bp != NULL && offset == 4) {
- regs->nip = bp->address + 4;
+ if (bp != NULL && (offset == 4 || offset == 8)) {
+ regs->nip = bp->address + offset;
atomic_dec(&bp->ref_count);
return 1;
}
@@ -787,10 +783,17 @@ static int xmon_sstep(struct pt_regs *regs)
static int xmon_break_match(struct pt_regs *regs)
{
+ int i;
+
if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) != (MSR_IR|MSR_64BIT))
return 0;
- if (dabr.enabled == 0)
- return 0;
+ for (i = 0; i < nr_wp_slots(); i++) {
+ if (dabr[i].enabled)
+ goto found;
+ }
+ return 0;
+
+found:
xmon_core(regs, 0);
return 1;
}
@@ -859,15 +862,13 @@ static struct bpt *in_breakpoint_table(unsigned long nip, unsigned long *offp)
{
unsigned long off;
- off = nip - (unsigned long) bpts;
- if (off >= sizeof(bpts))
+ off = nip - (unsigned long)bpt_table;
+ if (off >= sizeof(bpt_table))
return NULL;
- off %= sizeof(struct bpt);
- if (off != offsetof(struct bpt, instr[0])
- && off != offsetof(struct bpt, instr[1]))
+ *offp = off & (BPT_SIZE - 1);
+ if (off & 3)
return NULL;
- *offp = off - offsetof(struct bpt, instr[0]);
- return (struct bpt *) (nip - off);
+ return bpts + (off / BPT_SIZE);
}
static struct bpt *new_breakpoint(unsigned long a)
@@ -882,8 +883,7 @@ static struct bpt *new_breakpoint(unsigned long a)
for (bp = bpts; bp < &bpts[NBPTS]; ++bp) {
if (!bp->enabled && atomic_read(&bp->ref_count) == 0) {
bp->address = a;
- bp->instr[1] = bpinstr;
- store_inst(&bp->instr[1]);
+ bp->instr = (void *)(bpt_table + ((bp - bpts) * BPT_WORDS));
return bp;
}
}
@@ -895,47 +895,75 @@ static struct bpt *new_breakpoint(unsigned long a)
static void insert_bpts(void)
{
int i;
- struct bpt *bp;
+ struct ppc_inst instr, instr2;
+ struct bpt *bp, *bp2;
bp = bpts;
for (i = 0; i < NBPTS; ++i, ++bp) {
if ((bp->enabled & (BP_TRAP|BP_CIABR)) == 0)
continue;
- if (mread(bp->address, &bp->instr[0], 4) != 4) {
+ if (!mread_instr(bp->address, &instr)) {
printf("Couldn't read instruction at %lx, "
"disabling breakpoint there\n", bp->address);
bp->enabled = 0;
continue;
}
- if (IS_MTMSRD(bp->instr[0]) || IS_RFID(bp->instr[0])) {
+ if (IS_MTMSRD(instr) || IS_RFID(instr)) {
printf("Breakpoint at %lx is on an mtmsrd or rfid "
"instruction, disabling it\n", bp->address);
bp->enabled = 0;
continue;
}
- store_inst(&bp->instr[0]);
+ /*
+ * Check the address is not a suffix by looking for a prefix in
+ * front of it.
+ */
+ if (mread_instr(bp->address - 4, &instr2) == 8) {
+ printf("Breakpoint at %lx is on the second word of a prefixed instruction, disabling it\n",
+ bp->address);
+ bp->enabled = 0;
+ continue;
+ }
+ /*
+ * We might still be a suffix - if the prefix has already been
+ * replaced by a breakpoint we won't catch it with the above
+ * test.
+ */
+ bp2 = at_breakpoint(bp->address - 4);
+ if (bp2 && ppc_inst_prefixed(ppc_inst_read(bp2->instr))) {
+ printf("Breakpoint at %lx is on the second word of a prefixed instruction, disabling it\n",
+ bp->address);
+ bp->enabled = 0;
+ continue;
+ }
+
+ patch_instruction(bp->instr, instr);
+ patch_instruction(ppc_inst_next(bp->instr, &instr),
+ ppc_inst(bpinstr));
if (bp->enabled & BP_CIABR)
continue;
- if (patch_instruction((unsigned int *)bp->address,
- bpinstr) != 0) {
+ if (patch_instruction((struct ppc_inst *)bp->address,
+ ppc_inst(bpinstr)) != 0) {
printf("Couldn't write instruction at %lx, "
"disabling breakpoint there\n", bp->address);
bp->enabled &= ~BP_TRAP;
continue;
}
- store_inst((void *)bp->address);
}
}
static void insert_cpu_bpts(void)
{
+ int i;
struct arch_hw_breakpoint brk;
- if (dabr.enabled) {
- brk.address = dabr.address;
- brk.type = (dabr.enabled & HW_BRK_TYPE_DABR) | HW_BRK_TYPE_PRIV_ALL;
- brk.len = DABR_MAX_LEN;
- __set_breakpoint(&brk);
+ for (i = 0; i < nr_wp_slots(); i++) {
+ if (dabr[i].enabled) {
+ brk.address = dabr[i].address;
+ brk.type = (dabr[i].enabled & HW_BRK_TYPE_DABR) | HW_BRK_TYPE_PRIV_ALL;
+ brk.len = 8;
+ __set_breakpoint(i, &brk);
+ }
}
if (iabr)
@@ -946,20 +974,18 @@ static void remove_bpts(void)
{
int i;
struct bpt *bp;
- unsigned instr;
+ struct ppc_inst instr;
bp = bpts;
for (i = 0; i < NBPTS; ++i, ++bp) {
if ((bp->enabled & (BP_TRAP|BP_CIABR)) != BP_TRAP)
continue;
- if (mread(bp->address, &instr, 4) == 4
- && instr == bpinstr
+ if (mread_instr(bp->address, &instr)
+ && ppc_inst_equal(instr, ppc_inst(bpinstr))
&& patch_instruction(
- (unsigned int *)bp->address, bp->instr[0]) != 0)
+ (struct ppc_inst *)bp->address, ppc_inst_read(bp->instr)) != 0)
printf("Couldn't remove breakpoint at %lx\n",
bp->address);
- else
- store_inst((void *)bp->address);
}
}
@@ -1164,13 +1190,13 @@ static int do_step(struct pt_regs *regs)
*/
static int do_step(struct pt_regs *regs)
{
- unsigned int instr;
+ struct ppc_inst instr;
int stepped;
force_enable_xmon();
/* check we are in 64-bit kernel mode, translation enabled */
if ((regs->msr & (MSR_64BIT|MSR_PR|MSR_IR)) == (MSR_64BIT|MSR_IR)) {
- if (mread(regs->nip, &instr, 4) == 4) {
+ if (mread_instr(regs->nip, &instr)) {
stepped = emulate_step(regs, instr);
if (stepped < 0) {
printf("Couldn't single-step %s instruction\n",
@@ -1178,7 +1204,7 @@ static int do_step(struct pt_regs *regs)
return 0;
}
if (stepped > 0) {
- regs->trap = 0xd00 | (regs->trap & 1);
+ set_trap(regs, 0xd00);
printf("stepped to ");
xmon_print_symbol(regs->nip, " ", "\n");
ppc_inst_dump(regs->nip, 1, 0);
@@ -1330,14 +1356,14 @@ csum(void)
*/
static long check_bp_loc(unsigned long addr)
{
- unsigned int instr;
+ struct ppc_inst instr;
addr &= ~3;
if (!is_kernel_addr(addr)) {
printf("Breakpoints may only be placed at kernel addresses\n");
return 0;
}
- if (!mread(addr, &instr, sizeof(instr))) {
+ if (!mread_instr(addr, &instr)) {
printf("Can't read instruction at address %lx\n", addr);
return 0;
}
@@ -1349,6 +1375,35 @@ static long check_bp_loc(unsigned long addr)
return 1;
}
+static int find_free_data_bpt(void)
+{
+ int i;
+
+ for (i = 0; i < nr_wp_slots(); i++) {
+ if (!dabr[i].enabled)
+ return i;
+ }
+ printf("Couldn't find free breakpoint register\n");
+ return -1;
+}
+
+static void print_data_bpts(void)
+{
+ int i;
+
+ for (i = 0; i < nr_wp_slots(); i++) {
+ if (!dabr[i].enabled)
+ continue;
+
+ printf(" data "REG" [", dabr[i].address);
+ if (dabr[i].enabled & 1)
+ printf("r");
+ if (dabr[i].enabled & 2)
+ printf("w");
+ printf("]\n");
+ }
+}
+
static char *breakpoint_help_string =
"Breakpoint command usage:\n"
"b show breakpoints\n"
@@ -1382,6 +1437,9 @@ bpt_cmds(void)
printf("Hardware data breakpoint not supported on this cpu\n");
break;
}
+ i = find_free_data_bpt();
+ if (i < 0)
+ break;
mode = 7;
cmd = inchar();
if (cmd == 'r')
@@ -1390,15 +1448,15 @@ bpt_cmds(void)
mode = 6;
else
termch = cmd;
- dabr.address = 0;
- dabr.enabled = 0;
- if (scanhex(&dabr.address)) {
- if (!is_kernel_addr(dabr.address)) {
+ dabr[i].address = 0;
+ dabr[i].enabled = 0;
+ if (scanhex(&dabr[i].address)) {
+ if (!is_kernel_addr(dabr[i].address)) {
printf(badaddr);
break;
}
- dabr.address &= ~HW_BRK_TYPE_DABR;
- dabr.enabled = mode | BP_DABR;
+ dabr[i].address &= ~HW_BRK_TYPE_DABR;
+ dabr[i].enabled = mode | BP_DABR;
}
force_enable_xmon();
@@ -1437,7 +1495,9 @@ bpt_cmds(void)
for (i = 0; i < NBPTS; ++i)
bpts[i].enabled = 0;
iabr = NULL;
- dabr.enabled = 0;
+ for (i = 0; i < nr_wp_slots(); i++)
+ dabr[i].enabled = 0;
+
printf("All breakpoints cleared\n");
break;
}
@@ -1471,14 +1531,7 @@ bpt_cmds(void)
if (xmon_is_ro || !scanhex(&a)) {
/* print all breakpoints */
printf(" type address\n");
- if (dabr.enabled) {
- printf(" data "REG" [", dabr.address);
- if (dabr.enabled & 1)
- printf("r");
- if (dabr.enabled & 2)
- printf("w");
- printf("]\n");
- }
+ print_data_bpts();
for (bp = bpts; bp < &bpts[NBPTS]; ++bp) {
if (!bp->enabled)
continue;
@@ -1776,7 +1829,7 @@ static void prregs(struct pt_regs *fp)
#endif
printf("pc = ");
xmon_print_symbol(fp->nip, " ", "\n");
- if (TRAP(fp) != 0xc00 && cpu_has_feature(CPU_FTR_CFAR)) {
+ if (!trap_is_syscall(fp) && cpu_has_feature(CPU_FTR_CFAR)) {
printf("cfar= ");
xmon_print_symbol(fp->orig_gpr3, " ", "\n");
}
@@ -1938,8 +1991,13 @@ static void dump_207_sprs(void)
printf("hfscr = %.16lx dhdes = %.16lx rpr = %.16lx\n",
mfspr(SPRN_HFSCR), mfspr(SPRN_DHDES), mfspr(SPRN_RPR));
- printf("dawr = %.16lx dawrx = %.16lx ciabr = %.16lx\n",
- mfspr(SPRN_DAWR), mfspr(SPRN_DAWRX), mfspr(SPRN_CIABR));
+ printf("dawr0 = %.16lx dawrx0 = %.16lx\n",
+ mfspr(SPRN_DAWR0), mfspr(SPRN_DAWRX0));
+ if (nr_wp_slots() > 1) {
+ printf("dawr1 = %.16lx dawrx1 = %.16lx\n",
+ mfspr(SPRN_DAWR1), mfspr(SPRN_DAWRX1));
+ }
+ printf("ciabr = %.16lx\n", mfspr(SPRN_CIABR));
#endif
}
@@ -2130,6 +2188,25 @@ mwrite(unsigned long adrs, void *buf, int size)
return n;
}
+static int
+mread_instr(unsigned long adrs, struct ppc_inst *instr)
+{
+ volatile int n;
+
+ n = 0;
+ if (setjmp(bus_error_jmp) == 0) {
+ catch_memory_errors = 1;
+ sync();
+ *instr = ppc_inst_read((struct ppc_inst *)adrs);
+ sync();
+ /* wait a little while to see if we get a machine check */
+ __delay(200);
+ n = ppc_inst_len(*instr);
+ }
+ catch_memory_errors = 0;
+ return n;
+}
+
static int fault_type;
static int fault_except;
static char *fault_chars[] = { "--", "**", "##" };
@@ -2856,7 +2933,7 @@ generic_inst_dump(unsigned long adr, long count, int praddr,
{
int nr, dotted;
unsigned long first_adr;
- unsigned int inst, last_inst = 0;
+ struct ppc_inst inst, last_inst = ppc_inst(0);
unsigned char val[4];
dotted = 0;
@@ -2869,8 +2946,8 @@ generic_inst_dump(unsigned long adr, long count, int praddr,
}
break;
}
- inst = GETWORD(val);
- if (adr > first_adr && inst == last_inst) {
+ inst = ppc_inst(GETWORD(val));
+ if (adr > first_adr && ppc_inst_equal(inst, last_inst)) {
if (!dotted) {
printf(" ...\n");
dotted = 1;
@@ -2880,9 +2957,9 @@ generic_inst_dump(unsigned long adr, long count, int praddr,
dotted = 0;
last_inst = inst;
if (praddr)
- printf(REG" %.8x", adr, inst);
+ printf(REG" %.8x", adr, ppc_inst_val(inst));
printf("\t");
- dump_func(inst, adr);
+ dump_func(ppc_inst_val(inst), adr);
printf("\n");
}
return adr - first_adr;
@@ -3107,8 +3184,8 @@ static void show_task(struct task_struct *tsk)
(tsk->exit_state & EXIT_DEAD) ? 'E' :
(tsk->state & TASK_INTERRUPTIBLE) ? 'S' : '?';
- printf("%px %016lx %6d %6d %c %2d %s\n", tsk,
- tsk->thread.ksp,
+ printf("%16px %16lx %16px %6d %6d %c %2d %s\n", tsk,
+ tsk->thread.ksp, tsk->thread.regs,
tsk->pid, rcu_dereference(tsk->parent)->pid,
state, task_cpu(tsk),
tsk->comm);
@@ -3135,7 +3212,8 @@ static void show_pte(unsigned long addr)
unsigned long tskv = 0;
struct task_struct *tsk = NULL;
struct mm_struct *mm;
- pgd_t *pgdp, *pgdir;
+ pgd_t *pgdp;
+ p4d_t *p4dp;
pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep;
@@ -3159,28 +3237,26 @@ static void show_pte(unsigned long addr)
catch_memory_errors = 1;
sync();
- if (mm == &init_mm) {
+ if (mm == &init_mm)
pgdp = pgd_offset_k(addr);
- pgdir = pgd_offset_k(0);
- } else {
+ else
pgdp = pgd_offset(mm, addr);
- pgdir = pgd_offset(mm, 0);
- }
- if (pgd_none(*pgdp)) {
- printf("no linux page table for address\n");
+ p4dp = p4d_offset(pgdp, addr);
+
+ if (p4d_none(*p4dp)) {
+ printf("No valid P4D\n");
return;
}
- printf("pgd @ 0x%px\n", pgdir);
-
- if (pgd_is_leaf(*pgdp)) {
- format_pte(pgdp, pgd_val(*pgdp));
+ if (p4d_is_leaf(*p4dp)) {
+ format_pte(p4dp, p4d_val(*p4dp));
return;
}
- printf("pgdp @ 0x%px = 0x%016lx\n", pgdp, pgd_val(*pgdp));
- pudp = pud_offset(pgdp, addr);
+ printf("p4dp @ 0x%px = 0x%016lx\n", p4dp, p4d_val(*p4dp));
+
+ pudp = pud_offset(p4dp, addr);
if (pud_none(*pudp)) {
printf("No valid PUD\n");
@@ -3231,7 +3307,7 @@ static void show_tasks(void)
unsigned long tskv;
struct task_struct *tsk = NULL;
- printf(" task_struct ->thread.ksp PID PPID S P CMD\n");
+ printf(" task_struct ->thread.ksp ->thread.regs PID PPID S P CMD\n");
if (scanhex(&tskv))
tsk = (struct task_struct *)tskv;
@@ -3842,7 +3918,7 @@ static void sysrq_handle_xmon(int key)
xmon_init(0);
}
-static struct sysrq_key_op sysrq_xmon_op = {
+static const struct sysrq_key_op sysrq_xmon_op = {
.handler = sysrq_handle_xmon,
.help_msg = "xmon(x)",
.action_msg = "Entering xmon",
@@ -3869,10 +3945,9 @@ static void clear_all_bpt(void)
bpts[i].enabled = 0;
/* Clear any data or iabr breakpoints */
- if (iabr || dabr.enabled) {
- iabr = NULL;
- dabr.enabled = 0;
- }
+ iabr = NULL;
+ for (i = 0; i < nr_wp_slots(); i++)
+ dabr[i].enabled = 0;
}
#ifdef CONFIG_DEBUG_FS
diff --git a/arch/powerpc/xmon/xmon_bpts.S b/arch/powerpc/xmon/xmon_bpts.S
new file mode 100644
index 000000000000..69726814cd27
--- /dev/null
+++ b/arch/powerpc/xmon/xmon_bpts.S
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <asm/ppc_asm.h>
+#include <asm/asm-compat.h>
+#include <asm/asm-offsets.h>
+#include "xmon_bpts.h"
+
+/* Prefixed instructions can not cross 64 byte boundaries */
+.align 6
+.global bpt_table
+bpt_table:
+ .space NBPTS * BPT_SIZE
diff --git a/arch/powerpc/xmon/xmon_bpts.h b/arch/powerpc/xmon/xmon_bpts.h
new file mode 100644
index 000000000000..57e6fb03de48
--- /dev/null
+++ b/arch/powerpc/xmon/xmon_bpts.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef XMON_BPTS_H
+#define XMON_BPTS_H
+
+#define NBPTS 256
+#ifndef __ASSEMBLY__
+#include <asm/inst.h>
+#define BPT_SIZE (sizeof(struct ppc_inst) * 2)
+#define BPT_WORDS (BPT_SIZE / sizeof(struct ppc_inst))
+
+extern unsigned int bpt_table[NBPTS * BPT_WORDS];
+#endif /* __ASSEMBLY__ */
+
+#endif /* XMON_BPTS_H */
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.